Apparatus for bending elongated beam members are commonly found in the steel fabrication industry and can be generally categorized into two groups, those using a rotating wheel as a fulcrum and those using a fixed nonflexible arcuate surface as a fulcrum. U.S. Pat. No. 4,142,394 issued to Damman on Mar. 6, 1979 is exemplary of both groups. In FIGS. 1-3, Damman discloses a template having a longitudinally curved template face about which a strip length is bent by the upward movement of a press device. FIG. 5 of Damman shows a forming roll being used as a rotating fulcrum about which a strip length is bent.
U.S. Pat. No. 4,133,198 issued to Huda et al on Jan. 9, 1979 discloses an apparatus for bending boiler tubing about the arcuate surface of a cylindrically shaped part.
U.S. Pat. No. 3,396,565 issued to Miller on Aug. 13, 1968 discloses an arcuate shoe which is urged against a secured elongated tubular member to bend the member about the curvature of the shoe.
U.S. Pat. No. 2,371,393 issued to Horrigan on Mar. 13, 1945, discloses a matrix having a curved bending face against which a pipe is pressed and bent. The matrix has a plurality of openings which, in combination with a punch received within the pipe, corrugates the pipe to facilitate easier bending.
U.S. Pat. No. 2,347,593 issued to Cummings on Apr. 25, 1944 shows a pipe bending apparatus having a template with a curved bearing face. A pipe to be bent is fitted with a plurality of arcuate shoes which prevent the pipe from being cross-sectionally disfigured during bending. The shoes have a plurality of heels which contact the curved bearing face as the pipe is urged thereto and distribute the bending force across the shoe and consequently along the cross-section of the pipe.
U.S. Pat. No. 1,456,598 issued to Jackson on May 29, 1923 discloses a bending apparatus having an arcuate form against which a tubular pipe is urged and bent.
The common denominator of the aforementioned patents is that the devices disclosed are used to bend cylindrical tubular members or strips having solid rectangular cross-sections. Furthermore, the bending force exerted against the elongated member is concentrated, if only for a short period, at a singular point along the length of the elongated member. When such apparatus are used to bend elongated members having webs, flanges or rectangular tubular cross-sections, the force required to bend such beam members is usually greater than the force such webs, flanges or rectangular tubes can withstand at a singular point without being distorted. Consequently, what is needed is an apparatus for bending elongated beam members such as I-beams, channel members and rectangular tubing without distorting the same.